Superficial Face & Parotid Region Flashcards
The superficial muscles of the face develop from the _________ pharyngeal arch and are innervated by branches of the __________ nerve.
2nd pharyngeal arch
Facial nerve CN VII
Cutaneous innervation to the skin of the face is supplied via the terminal branches of the 3 divisions of CN V (GSA). Name them and the foramina they traverse to reach the skin.
Supraorbital n. from V1 via supraorbital foramen
Infraorbital n. from V2 via infraorbital foramen
Mental n. from V3 via mental foramen
What muscle of the scalp is responsible for wrinkling the forehead and is commonly a target of Botox injections?
Occipitofrontalis
The orbicularis oculi is composed of three parts, name them and give their functions.
Orbital part- tightly contracts skin around eye
Palpebral part- Palpebral reflex
Lacrimal part- acts on the lacrimal sac
The orbicularis oris muscle serves what function?
Closes, protrudes lips and puckers mouth.
The buccinator m. serves what function?
Muscle of cheek important to eating, drinking, blowing balloons, etc.
The levator labii superioris m. serves what function?
Elevates upper lip
Name the three “smile” muscles
Zygomaticus major, levator labi superioris, levator anguli oris
The levator anguli oris m. serves what function?
Pulls corner of mouth upward
The levator labii superioris alaeque nasi m. serves what function?
Elevates upper lip, flares nasal alar cartilages
The depressor labii inferioris m. serves what function?
Pulls lower lip down
The depressor anguli oris m. serves what function?
Pulls angle of mouth down
The mentalis muscle serves what function?
Pulls skin of chin upward
The platysma m. serves what function?
Elevates skin of thorax and neck
Describe the boundaries of the parotid bed.
Masseter m. anteriorly, zygomatic arch superiorly, pinna (auricle of ear) and SCM posteriorly.
Describe the course of the parotid duct as it leaves the anterior surface of the parotid gland inferior to the zygomatic arch.
The duct crosses the masseter m. and penetrates the buccinator m. to drain into the oral cavity at the level of the upper second molar tooth.
Within this structure, the trunk of the facial nerve divides into upper and lower divisions.
Parotid gland
What 3 neurovascular structures course deeply in the parotid gland?
Trunk and divisions of CN VII, retromandibular vein, upper part of external carotid artery.
Parasympathetic innervation to the parotid gland is via:
CN IX Glossopharyngeal N.
The preganglionics of CN IX travel in the __________ and __________ __________ branches of CN IX to synapse in the otic ganglion located in the roof of the infratemporal fossa.
Tympanic and lesser petrosal branches
The postganglionic fibers of CN IX travel with the _____________ branch of the Mandibular nerve (V3) to innervate the parotid gland for salivation.
Auriculotemporal branch
GSA innervation to the parotid fascia (parotid capsule) is mixed with contributions from the _______ branch of CN V and ______ ventral rami of the cervical plexus.
V3 of CN V
C2-C3 ventral rami of the cervical plexus
What muscle is responsible for squinting or winking? Be specific.
Orbital part of Orbicularis oculi m.
The parotid fascia (or capsule) is a superior continuation of the __________ fascia of the neck.
Cervical or deep investing fascia of the neck
This space is found deep between the parotid fascia and buccopharyngeal fascia and communicates with the retropharyngeal space medially.
Lateral pharyngeal space
Name the two divisions of CN VII (facial n.) that innervate the muscles of facial expression and their terminal branches.
Superior division (temporofacial):
Temporal
Zygomatic
Inferior division (cervicofacial):
Buccal
Mandibular
Cervical
Describe the innervation to the parotid gland.
- Parasympathetic innervation from the Glossopharyngeal n. (CN IX) via otic ganglion.
- GSA to the parotid fascia is mixed- cervical plexus (C2-C3 via great auricular n.) and also from the V3 division of CN V.
Cutaneous innervation of the face is via:
All 3 major divisions of the Trigeminal nerve:
V1- supraorbital n.
V2- infraorbital n.
V3- mental n.
The mental n. is a continuation of this nerve that travels through the mandible.
Inferior alveolar n.
The inferior alveolar n. is a continuation of this cranial nerve division.
V3 (Mandibular) from CN V (Trigeminal)
The minor trigeminal cutaneous branch, supratrochlear n., is a branch off this division of CN V.
V1 (Opthalmic)
This minor trigeminal cutaneous branch, zygomaticofacial n., is a branch off this division of CN V.
V2
The minor trigeminal cutaneous branch, buccal n., is a branch off this division of CN V and provides sensory innervation to the area around the cheek.
V3
The minor trigeminal cutaneous branch, auricotemporal n., is a branch off this division of CN V and innervates skin around the ear.
V3
The tympanic nerve is a branch of this CN:
CN IX- Glossopharyngeal
From what ganglion does the Tympanic n. arise?
Inferior ganglion of CN IX.
NOTE: no synapses occur in the superior and inferior ganglia, just multipolar cell bodies of GSA fibers to middle ear & post. 1/3 tongue tonsilar bed & oropharynx and GVA to carotid body in ganglia.
The superior ganglion of CN IX lies in this foramen:
Jugular foramen
The inferior ganglion of CN IX lies just inferior to this foramen:
Jugular foramen
What supplies GSA to the middle ear including the auditory tube?
Tympanic n. from CN IX- Glossopharyngeal
Beyond the bony canal and middle ear, fibers of the tympanic nerve continue on as the _______ ___________ nerve to the otic ganglion.
Lesser petrosal n.
Postganglionics from the otic ganglion to the parotid gland travel alongside fibers of this CN:
V3 of CN V
The lesser petrosal n. passes forward through the __________ part of the temporal bone and emerges through the hiatus of the lesser petrosal n. onto the floor or the middle cranial cavity.
Petrous
List the foramina CN IX traverses on its course to the otic ganglion.
- Jugular foramen
- Bony canal in bone separating carotid canal and jugular foramen
- Foramen ovale
What is the one and only place where pre and postganglionic fibers of CN IX synapse?
Otic ganglion
Preganglionic fibers of CN IX are found in which two nerves?
Tympanic & lesser petrosal nn.
The primary blood supply to the anterior face is via the _______ artery.
Facial artery
The facial artery is a major branch off the ________ ________ artery.
External carotid
The facial artery travels superficial or deep to the zygomaticus major m.?
Deep
The facial artery can share a common origin with this major branch of the ECA:
Lingual artery
The posterior auricular artery runs parallel to this muscle as it leaves the ECA:
Stylohyoid m.
The posterior auricular a. arises from the external carotid artery immediately above the _________ ________ of the digastric m.
Posterior belly of the digastric m.
Along its course, the ________ ________ artery supplies the parotid gland and the muscles of the styloid process and posterior belly of the digastric m.
Posterior auricular artery
The transverse facial artery is a branch off of this branch of the ECA:
Superficial temporal
The maxillary artery runs deep or superficial to to the mandible?
Deep
The superficial temporal artery has its start deep to this organ of the lateral face:
Parotid gland
The superficial temporal artery crosses the zygomatic arch at which point, anterior or posterior?
Posterior
The superficial temporal artery divides into _______ and ________ divisions after entering the temporal region of the scalp.
Frontal and temporal regions
Some of the blood supply to the area just above the nose and eyebrows actually derives from the ICA by way of the __________ artery which is located in the orbit.
Opthalmic artery.
There are two main routes for venous drainage from the face. Name them.
Internal jugular and external jugular.
The facial vein drains into the ________ jugular vein.
Internal jugular vein
These two veins join to form the retromandibular vein:
superficial temporal vein and maxillary vein.
The EJVein is formed by the confluence of ________ with _______ _________ vein.
retromandibular with posterior auricular vein.
Infections of the face can potentially spread to deep areas, including the brain through connections between:
Superficial veins with deeper plexuses including the pterygoid plexus and cavernous sinus.
The encapsulated mass of fat lying superficial to the buccinator m. at the anterior border of the masseter m. is called the:
Buccal fat pad
Two important structures cross superficial to the buccal fat pad. Name them.
Parotid duct and buccal branches of CN VII.
Parotid gland tumors are typically benign (80%), and involve the superficial or deep part of the gland?
Superficial
This nervous structure is in danger of being invaded by malignant parotid gland tumors:
CN VII (facial)
The most common nontraumatic cause of facial nerve paralysis is:
Inflammation of the nerve near its exit point at the stylomastoid foramen.
The most common cause of facial nerve paralysis is:
Bell’s Palsy- a common acute mononeuropathy
The pterygoid venous plexus drains into 3 veins/sinuses. Name them.
Facial v.
Maxillary v.
Cavernous sinus